Amidst diminishing federal investment in Adult Basic Education (ABE), there is growing interest in return on investment (ROI) as an economic rationale to support ABE funding. Against this backdrop, we provide an overview of the ROI concept and methods and the empirical evidence on ABE program impacts to broaden the discourse among practitioners and advocates. We point out that the most crucial building blocks necessary for ROI estimations are missing in the literature. We contextualize the current status of the literature by discussing challenges in ABE program evaluations and limitations in ROI methods. We then further our discussions by offering a recommendation for ROI estimation and alternative approaches to ROI. We conclude by calling for an expanded public discourse, beyond ROI, on the social benefits of funding ABE.